Proton-electron bremsstrahlung

The collision of energetic protons with free electrons is accompanied by the emission of bremsstrahlung. If the target electrons are approximately at rest, this process is designated electron-proton bremsstrahlung or suprathermal proton bremsstrahlung. The kinematics and the fully relativistic cross section of proton-electron bremsstrahlung in Born approximation is given. The X-ray spectrum produced by protons with a power-law spectrum is calculated for thin and thick targets.